Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
  • B60C9/00—Reinforcements or ply arrangement of pneumatic tyres
  • B60C9/02—Carcasses
  • B60C9/04—Carcasses the reinforcing cords of each carcass ply arranged in a substantially parallel relationship
  • B60C9/08—Carcasses the reinforcing cords of each carcass ply arranged in a substantially parallel relationship the cords extend transversely from bead to bead, i.e. radial ply
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
  • B60C9/00—Reinforcements or ply arrangement of pneumatic tyres
  • B60C9/02—Carcasses
  • B60C9/04—Carcasses the reinforcing cords of each carcass ply arranged in a substantially parallel relationship
  • B60C9/08—Carcasses the reinforcing cords of each carcass ply arranged in a substantially parallel relationship the cords extend transversely from bead to bead, i.e. radial ply
  • B60C9/09—Carcasses the reinforcing cords of each carcass ply arranged in a substantially parallel relationship the cords extend transversely from bead to bead, i.e. radial ply combined with other carcass plies having cords extending diagonally from bead to bead, i.e. combined radial ply and bias angle ply
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T152/00—Resilient tires and wheels
  • Y10T152/10—Tires, resilient
  • Y10T152/10495—Pneumatic tire or inner tube
  • Y10T152/10855—Characterized by the carcass, carcass material, or physical arrangement of the carcass materials
  • Y10T152/10864—Sidewall stiffening or reinforcing means other than main carcass plies or foldups thereof about beads

Definitions

• the invention relates to tires with a metal carcass reinforcement and more particularly to the reinforcement of such tires in their sidewalls.
• the tires intended for uses on heavy vehicles comprise a carcass reinforcement formed of at least one ply of metal reinforcements embedded in a rubber material, this reinforcement having the role of resisting the pressure. internal inflation of the tire.
• This carcass reinforcement is anchored at its ends in tire beads intended to come into contact with seats of a mounting rim.
• the anchoring of the carcass reinforcement may in particular be made by winding around a bead circumferential reinforcement such as a bead wire.
• a carcass reinforcement is said to be radial in the present document since the reinforcements which compose it make an average angle greater than 75 degrees with the circumferential direction.
• the tire comprises, radially beyond the beads, flank areas undergoing cycles of curvature variations during rolling at each passage in the contact with the roadway.
• the carcass reinforcement is also surrounded by a crown reinforcement formed by the stacking of several layers of reinforcements, these reinforcements being generally crossed between them from one sheet to the next, this crown reinforcement being itself radially surmounted. on the outside by a tread intended to be in contact with the road during the rolling of the tire.
• This mechanism can occur for example in the case of use of tires in twin tires, one of the tires being partially or completely deflated and the other remaining inflated.
• the carcass reinforcement of the deflated tire is subjected to a low or zero tension, given the absence of inflation pressure, while being subject to variations in curvature.
• the present invention seeks at the same time to limit the fatigue of the metal reinforcements of the carcass reinforcement and to limit the surge pressure wave resulting from a burst at the time of reinflation of a tire whose reinforcement carcass would have been fatigued by its metal reinforcements.
• An objective of this invention is to combine a reduction of the fatigue of the carcass metal reinforcements under severe rolling conditions, with a limitation of a possible excess pressure generated in the vicinity of the tire following the release of energy resulting from the propagation of the rupture of the carcass reinforcement.
• a vehicle tire carrying heavy load the tire delimiting an internal inflation cavity and comprising a radial carcass reinforcement surmounted radially on the outside by a crown reinforcement, the reinforcement of carcass being formed by a plurality of metal reinforcements embedded in a rubber-coating material, the reinforcements of the carcass reinforcement making an angle of at least greater than 75 ° with the circumferential direction.
• This tire further comprises beads intended to be in contact with a mounting rim, the carcass reinforcement being anchored in these beads.
• This tire comprises two sidewalls, each side extending between a bead and the top, the two sidewalls comprising a first additional frame which can be arranged between the carcass reinforcement and the internal cavity of the tire (that is to say at inside the carcass reinforcement) or axially outside the carcass reinforcement (i.e. outside the carcass reinforcement) and at least one of the flanks comprising a second additional reinforcing reinforcement.
• the first additional reinforcement comprises a plurality of reinforcements of textile nature oriented at an angle at least equal to 80 degrees and at most 90 degrees with the circumferential direction.
• the second additional armature comprises, in the circumferential direction and alternately, a plurality of first parts and second parts, at least one of these parts comprising a plurality of coated reinforcements in a rubber material, these reinforcements being oriented in a direction close to or identical to that of reinforcements of the carcass reinforcement.
• the width of each second part of the second reinforcement measured at the points of the second radially innermost additional reinforcement is at least 20 mm, this width being measured in a direction perpendicular to the circumferential direction on the tire.
• the width of a reinforcement portion may be measured on the semi-finished product prior to its incorporation into the manufacture of the tire; on the tire this width may correspond substantially to the width measured at the points of said armature radially innermost, that is to say the closest to the axis of rotation.
• the width of the second parts is much greater than the distance between each reinforcement in the armature. (0012)
• Each of these parts has its own breaking strength, i.e., a breaking force per unit width of reinforcement (this width being measured in the circumferential direction that is to say in a direction perpendicular to the reinforcements when these make an angle of 90 degrees with the circumferential direction).
• This second frame is formed so that the breaking strength of the second parts is less than the breaking strength of the first parts.
• first additional reinforcement and the second additional reinforcement are placed on either side of the carcass reinforcement (if the first additional reinforcement is placed inside the carcass reinforcement, it is ie between the carcass reinforcement and the internal cavity of the tire, then the second additional reinforcement is placed outside the carcass reinforcement).
• the first additional reinforcement makes it possible to limit the deformation (avoiding excessive curvatures) of the carcass reinforcement during a pressure drop of the tire and the second reinforcement by its own structure makes it possible to limit the extent of any breakage of the carcass reinforcement.
• the second additional reinforcement using a succession of first parts and second parts having different tensile strengths, it is possible to form a kind of barrier to the propagation, in the circumferential direction, of the rupture of the elements. reinforcements of the carcass reinforcement, by limiting the total circumferential length of the opening. It has surprisingly been found that by significantly reducing the circumferential length of the opening of the sidewall of the tire, it is possible to reduce the blast effect produced by the bursting of the tire.
• the first additional reinforcement is placed between the carcass reinforcement and the rubber material ensuring the sealing of the internal cavity of the tire inside which the inflation pressure is exerted (ie ie inside the carcass reinforcement).
• these first and second armatures extend in the radial direction (perpendicular to the axis of rotation) over a height at most equal to 80% of the section height of the body. tire.
• the section height of the tire is measured when the tire is mounted on its mounting rim and inflated to its operating pressure between the radially innermost points of the beads and the radially most radially carcass reinforcement points. outside.
• the width of the second parts of the second reinforcement, at the points of the second radially innermost additional reinforcement is at least 20 mm and at most equal to 60 mm and the sum of the widths of the second reinforcement a first portion 51 and a second portion 52 is at least 40 mm and at most equal to 80 mm.
• the first additional reinforcement is advantageously made of textile reinforcements chosen from reinforcements made of polyamide or aramid, polyketone, polyester, rayon; they can also be hybrid in nature, that is to say formed with at least two textile cords of different natures.
• the first additional reinforcement comprises a succession of first parts and second parts having different tensile strengths, these tensile strengths being measured over a unit width of reinforcement taken in the circumferential direction.
• the first and second additional reinforcement extend in at least one of the flanks radially on either side of the points axially the outermost when the tire is mounted on its mounting rim and inflated to its operating pressure.
• the second armature is in the sidewall of the tire which, when the tire is mounted on a vehicle, is on the outside of said vehicle.
• the first and second additional reinforcements are able to withstand the bending cycles that undergoes the carcass reinforcement; by being able to withstand the bending cycles, it is meant that the reinforcements composing these additional reinforcements substantially retain their resistance to breaking in the initial state.
• the reinforcements of the first and second additional reinforcements are chosen from reinforcements of a textile nature.
• the reinforcements (especially those of the first parts) of the second additional reinforcement may be metallic provided that the diameter of the elementary wire is appropriate to achieve a flexural fatigue strength much greater than that of reinforcements of the carcass reinforcement.
• the first additional reinforcement of a tire according to the invention comprises, seen in a meridian section plane (that is to say containing the axis of rotation), two ends, this first additional reinforcement s extending between these two ends in at least one of the flanks at least between a point situated radially inside the axially outermost point of the profile of the carcass reinforcement of the tire mounted on its mounting rim and inflated to its use pressure, and a point located in the vicinity of an axial end of the crown reinforcement.
• first additional reinforcement is positioned outside the carcass reinforcement, it is preferable that its radially outward end is distant from the end of the crown reinforcement by a distance of at least 10 mm. mm. (0024)
• textile reinforcements of greater resistance to break than those of the textile reinforcements of the second parts of the same second additional reinforcement may be oriented in the meridian direction, that is to say in a plane containing the axis of rotation of the tire, or in any other direction.
• the second additional reinforcement comprises only a plurality of first parts, each formed by a web of textile reinforcements, these first parts being disjoint from each other in the direction circumferentially.
• the textile reinforcements are arranged radially on the tire, that is to say in a direction forming an angle equal to 90 degrees with the circumferential direction on the tire.
• the space between two first parts corresponds to a second part of breaking strength. equal to zero.
• These second parts have no reinforcing element or even rubber mixture. This variant is particularly suitable in the case where the first parts comprise metal reinforcements.
• the second parts of the second frame may be constituted by the same rubber mixture as that of the first parts to facilitate the installation of the additional reinforcement during manufacture of the tire.
• the width of these second parts is much greater than the distance separating each reinforcement from the first parts of the second armature; this width is at least ten times greater than this distance between each reinforcement and preferably greater than 20 mm on the semi finished product before its incorporation into the manufacture of a tire according to the invention.
• the second additional reinforcement is a sheet of rubber mixture reinforced by textile reinforcements parallel to each other, these textile reinforcements being cut at least at a location of their length over a plurality of regions of said tablecloth.
• region here means that on a given width of the ply corresponding to the width of said region (and measured perpendicularly to the reinforcements of the additional reinforcement), the reinforcements are all cut so as to create, in said additional reinforcement, a second part of low breaking strength.
• the at least one cut on a reinforcement is located so as to be located in the sidewall of the tire in the region of said flank corresponding to the point of the axially outermost carcass reinforcement.
• the second additional reinforcement is reinforced, in the second parts of low tensile strength, by discontinuous reinforcements oriented in a direction making an angle equal to or close to 90 degrees with the circumferential direction. These discontinuities can easily be obtained after making this additional reinforcement with continuous reinforcements by cutting in several places each of the reinforcements to form second parts.
• the second additional reinforcement is a sheet of rubber mixture reinforced with a succession of reinforcements of different types having different tensile strengths, these reinforcements being arranged substantially parallel to each other. Reinforcements of the same kind are grouped together to form parts of appropriate circumferential average length. These breaking strength portions are alternately arranged in the circumferential direction.
• the textile reinforcements of the second additional reinforcement are chosen from reinforcements made of polyamide, aramid or polyketone; they can also be hybrid in nature, that is to say formed with at least two textile cords of different natures.
• the second additional reinforcement can be indifferently positioned on one side or the other of the carcass reinforcement, it is advantageous to position it so that the carcass reinforcement is between this second additional reinforcement and the internal cavity of the tire inside which the inflation pressure of the tire is exerted. It is also possible to provide a decoupling material between the carcass reinforcement and this second additional reinforcement.
• Figure 1 partial view of a sidewall of a radial carcass reinforcement tire, of the prior art, after burst test;
• Figure 2 meridian sectional view of a tire according to the prior art
• Figure 3 meridian sectional view of a tire according to the invention.
• Figure 4 partial sectional view along the line II-II of a sidewall of the tire of Figure 3;
• FIG. 2 partial sectional view of a variant of the invention.
• This tire is reinforced by a carcass reinforcement 2 itself formed of a plurality of reinforcements 21 oriented so as to make an angle of 90 degrees with the circumferential direction (direction which is perpendicular to the plane of Figure 2).
• the reinforcements 21 of the carcass reinforcement are assemblies of 19 threads 0.18 mm in diameter without a band around said reinforcements.
• the carcass reinforcement extends in the vertex 3 and is surmounted radially on the outside by a crown reinforcement 31; the carcass reinforcement extends in the flanks 1 and ends with an anchorage in the beads 4.
• FIG. 1 partially shows one of the flanks 1 of the tire shown in Figure 2 after undergoing a burst test.
• This test consists, after having previously cut carcass reinforcements 21 over a circumferential length L between 30 to 80 mm (measured substantially at the axially outermost point of the tire), to mount the tire on a wheel and to inflate. this tire until it burst.
• burst pressure and sound pressure are measured at a distance of 1 m from the tire.
• the circumferential length of the opening 22 is measured on the sidewall of the tire.
• the measured acoustic pressure reaches a value of 4.5 bar for a pressure bursting of 14 bars.
• the circumferential length of the opening after burst is equal to 550 mm.
• the measured acoustic pressure reaches a value of 3.5 bar for a burst pressure of 9 mm. bars.
• the circumferential length of the opening after burst is equal to 450 mm.
• FIG. 3 A tire 10 according to the invention is shown with FIG. 3. This tire comprises in each sidewall 1, two additional armatures extending both between the vicinity of the axial end of the crown reinforcement and the vicinity of a bead.
• a first additional reinforcement 6 substantially follows the profile of the carcass reinforcement 2 and is placed inside the carcass reinforcement (that is to say between said reinforcement and the internal cavity of the tire with the inside of which is exerted the inflation pressure of the tire).
• This first frame 6 is composed of aramid textile reinforcements oriented in the tire so as to make a 90-degree angle with the circumferential direction (in this case each reinforcement is substantially contained in a plane containing the axis of rotation).
• the textile reinforcements of this first additional reinforcement 6 have a density of 100 reinforcements per decimetre of reinforcement approximately (this density being measured perpendicular to the reinforcements on the reinforcement before laying in manufacture)
• the first additional reinforcement is coupled to the carcass reinforcement by a thickness of rubber material whose average thickness is greater than the average thickness of said first additional reinforcement.
• a second additional reinforcement 5 is placed axially outside the carcass reinforcement.
• This additional reinforcement 5 extends over a radial length H, in the plane of FIG. 3, on either side of the point E of the axially outermost carcass reinforcement when the tire is inflated at its nominal pressure.
• This second additional reinforcement 5 ends radially outside in the vicinity of the crown reinforcement 31.
• the first additional reinforcement 6 extends in the example shown on the same radial length equal to H. Of course, it does not It is not essential that these two additional reinforcements are of the same length. It is advisable that the first additional reinforcement supporting the carcass reinforcement extends from the bead of the tire to the crown reinforcement.
• FIG. 4 there is shown a section of a sidewall 1 of the tire 10 shown in Figure 3.
• the first additional reinforcement 6 is composed of a plurality of reinforcements 60 spaced in the circumferential direction (arrow F in FIG. 4) of the same distance.
• the second additional armature 5 is formed of a succession of first portions 51 of width La and second portions 52 of width Lb, these portions being arranged alternately (a first portion 51 follows in the circumferential direction a second portion 52 ).
• the first portions 51 have a breaking strength when subjected to force in the direction of the reinforcements (i.e.
• Rupture strength means the breaking force in daN per unit length in decimetres (dm) (the breaking strength of a reinforcement reinforced reinforcement is substantially equal to the breaking force of each reinforcement multiplied by the number of reinforcements per decimetre).
• Each first portion 51 is constituted by a rubber material reinforced by cables parallel to each other.
• the cables are arranged so as to obtain, in the manufacture of the frame, 80 cables per decimeter.
• the cables are Aramide 330 * 2 - 230/230 and have a breaking strength of the order of 100 daN.
• the installation pitch is 1.25 mm including the average diameter of the cable and the rubber bridge between two successive cables: the average distance between two cables is consequently less than 1 mm.
• Each first portion 51 is of average width Equal to 25 mm. This width is measured on the frame before its incorporation into the manufacture of the tire. This width may correspond substantially to the width at the points radially the innermost of the second additional reinforcement 5 in the tire, since these points are relatively close to the bead.
• the width of each second part at any point of a tire meridian profile is greater than 20 mm and increases radially points closest to the axis of rotation towards the points radially most important. outside.
• a decimetre of web comprises about 80 reinforcements per decimeter (dm); these parts A consequently have a breaking strength (Fr A ) equal to 8000 daN / dm.
• Each second portion 52 of width Lb equal to 50 mm, is formed with the same rubber mixture which binds the reinforcements of the first parts 51 but without any reinforcement.
• the breaking force of the second parts is much lower than that of the first parts since it is substantially equal to the breaking force of the rubber mixture, that is to say 20 daN / dm for identical thickness levels.
• the breaking strength of the first parts 51 of the second additional reinforcement 5 is at least 3000 daN / dm and even more preferably at least 5000 daN / dm for a tire intended to equip a vehicle weight heavy.
• the breaking strength of the second parts 52 of the second additional reinforcement 5 is at most equal to 300 daN / dm and even more preferably at most equal to 100 daN / dm.
• the adaptation of the invention to a conventional tire size for a truck is easy for the person skilled in the art, knowing that preferably the width of a part of lower breaking strength is between 20 and 60 mm and even more. more preferably between 30 and
• first portion 51 and a second portion 52 is at least equal to 40 mm and at most equal to 80 mm which allows to obtain, in the test performed to cut a high proportion of reinforcements of the carcass reinforcement on a width L of 80 mm, an opening length of the flank at burst of less than 150 mm and thus to limit the overpressure to 1 meter to a value less than 1 bar.
• Figure 5 shows a variant of the invention according to which the first armature 6 comprises first and second parts 61 and 62 of different strengths.
• the first portions 61 of high strength comprise reinforcements oriented in the sidewall to make a 90 degree angle with the circumferential direction (i.e. each reinforcement of these first parts is substantially contained in a plane containing the rotation axis of the tire).
• the second parts 62 of the first additional reinforcement 6 are devoid of reinforcements.
• the first portions 61 of high strength are arranged to be circumferentially in coincidence with the second portions 52 (of low resistance in the direction perpendicular to the plane of the figure).
• the first additional reinforcement (6) comprises first parts (61) of greater resistance to rupture than second parts (62), different stiffnesses (61, 62), these first and second portions being arranged to be circumferentially out of phase with first and second second portions (51 and 52) of the second additional reinforcement (5), the first portions (51) being of greater tensile strength than the second portions (52).
• the tire according to the invention comprises a first additional reinforcement composed of a plurality of discontinuous reinforcements in the circumferential direction.
• each additional reinforcement can be extended on either side of the flanks to go under or on the crown reinforcement and in the beads.
• the device of the invention is particularly interesting when the tire has a large internal cavity volume, associated with a high level of inflation pressure, as is the case in tires for heavy vehicles, aircraft, for construction or civil engineering machinery.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Tires In General (AREA)

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• 2008
  • 2008-05-07 FR FR0853022A patent/FR2930910B1/fr not_active Expired - Fee Related
• 2009
  • 2009-05-05 JP JP2011507891A patent/JP5474935B2/ja not_active Expired - Fee Related
  • 2009-05-05 CN CN2009801162778A patent/CN102015329B/zh active Active
  • 2009-05-05 WO PCT/EP2009/055409 patent/WO2009135836A1/fr active Application Filing
  • 2009-05-05 EA EA201071274A patent/EA017413B8/ru not_active IP Right Cessation
  • 2009-05-05 EP EP09742054A patent/EP2285594B1/fr active Active
  • 2009-05-05 US US12/991,384 patent/US8613300B2/en active Active
  • 2009-05-05 BR BRPI0912214A patent/BRPI0912214A8/pt not_active Application Discontinuation
  • 2009-05-05 AT AT09742054T patent/ATE538950T1/de active

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